The invention relates to a method and apparatus for producing successive transverse lines of image points on the surface of a recording medium. In systems of this type, relative movement is effected between a recording medium and a row of light-emitting elements, for example LED's. The LED's are energized by control signals which determine the image points in a single transverse line of image points to be formed on the recording medium.
A system of this type is disclosed, for example, in Swiss patent No. 568,593. In that system, the number of LED's in the LED-row is equal to the number of image points in the transverse line of image points to be formed on the recording medium. Due to the relatively large dimensions of the individual LED's, the number of LED's which can be contained within a single LED-row, and accordingly the resolution of the resultant image, is quite limited.